Sectionalizing switch gear



Dec. 13, 1955 TURNER 2,727,105

SECTIONALIZING SWITCH GEAR Filed Oct. 12, 1951 2 Sheets-Sheet l FIG.I.

Dec. 13, 1955 J. L. TURNER SECTIONALIZING SWITCH GEAR 2 Sheets-SheetFiled Oct. 12, 1951 United States Patent SECTIONALIZENG swrrcrr GEARJohn L. Turner, t. Louis, Mo, assign-or, by mesue assignments, to A. B.Chance Company, entraha, Mo, a corporation of lVIiss curi ApplicationOctober 12, E 51, Serial No. 250,999

4 Claims. (Cl. 230-425) This invention relates to sectionalizing switchgear, and more particularly, to outdoor disconnect switch gear for useat the junction of at least three overhead conductors in a powertransmission system. It is an improvement upon structures such as shownin the U. S. Patent 2,470,576 of Pollock et al. entitled Gang OperatedSwitch, dated May 17, 1949, and in my copending U. S. patent applicationSerial No. 247,320, filed September 19, 1951, for Quick-Break Switch.

Among the several objects of this invention is the provision of simpleand compact switch gear of the type described adapted to sectionalize ahigh-voltage transmission line and at the same time provide fordisconnecting a feeder from the line without interrupting the line; theprovision of switch gear of this type adapted to form a sectionalizingjunction for two feeders with a supply line; the provision of suchswitch gear providing improved safety; and the provision of such switchgear permitting economy in power transmission systems by elimination ofequipment heretofore required at substations.

To accomplish these objectives 1 have provided switch gear comprising aframe adapted to be mounted upon a pole generally at the level of theoverhead conductors. The frame has a crossarm and a cantilever extendingtransversely from the crossarm. First and second line terminals arelocated at the ends of the crossarm and a third line terminal is locatedat the outer end of the cantilever. Each line terminal is in the form ofa connector on a fixed insulator carrying a switch contact and to whichis connected a conductor. First and second rotary insulators are locatedintermediate the ends of the cantilever adjacent the first and secondline terminals, respectively, and a third rotary insulator is supportedintermediate the ends of the cantilever adjacent the third lineterminal. A switch blade is fixed to each of the rotary insulators forcooperation with the contact on the adjacent fixed insulators; and a busbar, which is supported upon the rotary insulators, permanently connectsall of the switch blades in common. More specifically, the switch ladesare connected to the bus bar by a wiping brush arrangement. Otherfeatures will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations ofelements, features of construction, and arrangements of parts which willbe exemplified in the structures hereinafter described, and the scope ofwhich will be indicated in the following claims.

In the accompanying drawings, in which one of various possibleembodiments of the invention is illustrated,

Fig. l is a circuit diagram of a power transmission system incorporatingthe switch gear of this invention;

Fig. 2 is a perspective view of the switch gear;

Fig. 3 is a top plan view of the device shown in Fig. 2; and,

Figs. 4 and 5 are detailed top and side views showing the connectionbetween a switch blade and the bus bar.

Similar reference characters indicate corresponding parts throughout theseveral views of the drawings.

ICQ

It will be understood that, in power transmission systems, oil circuitbreakers or switches are located at the generating stations and thesubstations to open the circuits under load, and that disconnectswitches are employed in conjunction with the oil circuit breakers toisolate various portions of the system for purposes of inspection andrepair. In high voltage systems, outdoor type disconnect switches areused because they economically permit the wide separation of conductiveparts necessitated by such high voltages.

In setting out the features of this invention, reference is made to Fig.l, which illustrates one phase of a typical power system incorporatingthe switch gear of this invention employed in several different ways, byway of example. There is a loop circuit L supplied from supply feedersF1 and F2. The latter connect with suitable sources of supply (notshown). The supply feeder F1 is connected to a straight section of theloop L by a switching device S1 of this invention having a line terminalI. connected to the supply line and other line terminals 3 and 5connected to sectionalize the loop. The other supply feeder F2 isconnected at a corner of the loop circuit to a terminal 5 of switch gearS2. The other line terminals 1 and 3 of the switch gear S2 are connectedto sectionalize the loop L. The loop circuit in turn supplies lateralfeeders F3, F4 and F5. These feeders are connected to the line terminals1 of switching devices S3, S4 and S5, respectively, and the lineterminals 3 and 5 of the switching devices S3, S4 and S5 are connectedto sectionalize the loop.

The feeders F3, F4 and F5 lead to substations, one of which is shown atSS. Such a substation generally includes a transformer T for reducingthe voltage, an oil switch or oil circuit breaker OS for opening thecircuit under load and a bus B to which are connected distributionfeeders D1 The latter distribute 12' wet to consumers.

As will be shown, the switch gear of this invention as exemplified atS1, S2, S3, S4 and S5- permits any part of the system to be taken out ofservice or sectionalized without interfering with the operation of theremainder of the syst m. An additional advantage or" my switch gear isin the economy of equipment. Heretofore, it has been necessary to locatea disconnect switch at the substation SS to permit inspection and repairof the substation. Increased safety is also afforded in that allconductors at a junction point may be disconnected independently of oneanother.

The switch gear of the invention shown diagrammatically in Fig. l isfully illustrated in Figs. 2-5. it will be understood, however, that thedisclosure is for one line or phase and that, in a three-phase system,there may be three devices mounted in vertically spaced relation upon acommon pole and concurrently operated by common control rods.

Referring to Figs. 2 and 3, each switching device comprises a frame 9secured to a pole 7. The frame 9 has a horizontal crossarm 1i and acantilever l3 projecting transversely of the crossann from the pole. Thecantilever is formed by a pair of spaced horizontal arms 15 whichconverge to a common end 17. At la is a verti cal channel-type member towhich is secured the crossarm 13 and by means of which the entire frame9 is secured to the pole. inclined struts 21 brace the crossarm 11 onthe channel member and struts Z3 brace the cantilever 13 with thechannel member. A T-shaped brace 25 is formed at the outer end of thecantilever.

The frame forms a support for three horizontal break switches adapted toconnect together three overhead conductors 2'7, 29 and 31 leading to andsupported by the frame. Conductors 29 and 31 are generally aligned withthe crossarm 11 of the frame, whereas the conductor 27 is generallytransverse or lateral to the other conductors and is supported from theend 17 of the cantilever. The three conductors 27, 29 and 31 areconnected to the line terminals 1, 3 and 5, respectively, whichcooperate respectively with movable terminals 33, 35 and 37 to form theaforementioned horizontal break switches. The fixed terminals and 3 arelocated at the ends of the crossarrn 11, and the fixed terminal 1 islocated at the end 17 of the cantilever. The movable terminals 33, and37 are located on the cantilever intermediate its ends with the movableterminal 33 being relatively adjacent the fixed terminal 1, the movableterminal 35 being relatively adjacent the fixed terminal 3 and themovable terminal 37 being relatively adjacent the fixed terminal 5.

Each of the fixed terminals comprises a pin-type insulator 39 projectingvertically upward and carrying at its upper end a switch contact clip 41of the enclosed floating contact type. Each of the conductors ismechanically supported from the frame by means of an outrigger string ofsuspension insulators 43 tied to an extremity of the frame, and eachconductor is electrically connected to the contact 41 at the adjacentterminal by means of a jumper 45 secured by a clamp 47 extending fromthe contact. It will therefore be seen that both the conductors and thecontacts are supported by the frame in insulated relation therefrom.

Each of the movable terminals comprises a pin-type insulator 49projecting vertically upright from a thrust bearing 51 secured in thecantilever portion 13 of the frame. 1 he thrust bearings 51 for themovable terminals 35 and 37 are fastened in the arms 15 of the frame,and the thrust bearing for the movable terminal 33 is fastened in theT-shape brace 25.

The movable terminals are controlled by means of operating rods 53 whichextend from the frame member downward along the pole 7 for operationfrom ground level. As shown, there is an operating rod for each movableterminal, the rods being disposed around the pole in the same relativelocation as the fixed terminals 1, 3 and 5. Handles 55 may be attachedto the bottom of the operating rods 53, or the rods may be under thecontrol of some type of automatic motor means. Each rod extends througha thrust bearing 57 carried on a bracket 59 fastened to the crossarm 11.

Sleeves 61 are fastened to the tops of the operating rods 53, forexample by set screws. Cranks 63 are fastened to the sleeves 61 to driveconnecting links 65 reaching toward the three movable terminals. Thelinks 65 are connected at their other ends to second cranks 67 which arefastened to the rotary insulators 49. Each rotary insulator 4'9 isthereby rotated by an operating rod 53 from ground level.

To the top of each of the rotary insulators 49 there is fastened at 6-3a bracket 69 which clamps one end of a switch blade 71. for eachterminal. Each switch blade 71 is flattened at its other end to enter amouth 73 in the contact clip 4i mounted upon the adjacent fixedinsulator 39. As shown, the months 73 of the contact clips on the threefixed terminals are arranged so that the switch blades may swingoutwardly therefrom. For example, the switch blade for the movableterminal 35 swings'outwardly from the end of the crossarm to theposition indicated by dotted lines. Similarly, the switch blade for themovable terminal 37 swings outwardly away from the other end of thecrossarm. The switch blade for the movable terminal 33 swingscounterclockwise as viewed in Fig. 3 toward the movable switch terminal35. In order to prevent interference between the switch blades for themovable terminals 33 and 35, the switch blade for the movable terminal33 and the associated switch parts are in a plane slightly elevated withrespect to the switch parts for the terminals 35 and 37 (Fig. 2).

Arcing horns are provided to interrupt arcs formed in opening theswitches. it will be understood that although a circuit breaker isemployed to openthe circuit under load, there may be charging currentresulting from the line capacitance and transformer exciting current tobe interrupted by the disconnect switches. The arcing horns aredescribed in detail in the aforementioned patent application, butbriefly include a cantilevered spring whip 75 formed of a resilientelectrically conductive rod having one end coiled into a helical coilspring with the axis of the spring transverse to the length of the whip.The spring is contained in a spring housing 77 attached to the switchblade 71 and is in electrically conductive relation with the switchblade.

Mounted on each contact 41 is a fixed arcing horn 79 formed as a detentfor the spring whip 75 of the respective switch blade. This fixed arcinghorn 79 is adapted to provide a delayed quick opening action with thespring whip 75 after withdrawal of the switch blade 71 from its contactclip 41. As explained in the aforementioned patent application, the endof the whip 75 is caught in a notch 81, so formed and positioned withrespect to the whip that the free end of the whip becomes wedged in thenotch and is withdrawn in an axial direction upon opening of the switchblade. In closing the switch blade, the whip rides up a cam 83 formed onthe fixed arcing horn and drops into the aforementioned notch.

The three switch blades are permanently connected together by means of abus bar 85 supported on the rotary insulators of the three movableterminals. As shown in Fig. 4, each of the rotary insulators 49 has astud 87 projecting upwardly through the attached bracket 69. A contactplate 89 is supported on the stud 87 by lock nuts 91in such manner as topermit rotation, and the three contact plates are jointed together byconductive straps 91. The brackets 69 in turn carry brushes 93 securedat 68 and having inserts 95 of silver or the like which engage annularinserts 97 of silver or the like secured to the bottom surface of thecontact plates 89. The contact plates thereby serve as sleet hoods forthe wiping surfaces, and the elimination of pigtails provides for longlife and safety against accidental grounding with the frame.

Referring back to Fig. 1, the switch gear is particularly adapted toprovide improved sectionalizing action. As an example, the supply feederF1 is shown disconnected at terminal 1 of the switch gear S1 to permitrepair of the feeder while at the same time the loop L is maintainedclosed through line terminals 3 and 5 of the device S1. As anotherexample, a portion of the line betweenthe devices S2 and S5 isdisconnected at their terminals 1 and 5, respectively, withoutinterfering with the supply from feeder F2 or the supply to feeder F5.Additionally, it will be noted that the substation SS may be taken offthe line by opening the device S3 at terminal 1. Therefore, there is noneed to have a disconnect switch at the substation as requiredheretofore. Moreover, the substation is not only disconnected at S3 butthe feeder F3'1eading' into the substation is disconnected so that aWorker is afforded complete safety.

The structure for carrying out the invention is simple and compact, thestationary insulators at 1, 3 and 5 being arranged on the corners of atriangle within the confines of which the group of rotary insulators ismounted.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As many changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

I claim:

1. Sectionalizing switch gear for use at a group of three overhead lineterminals two of which are in a first loop circuit and one of which isin a second feeder of tap circuit; comprising a single structure adaptedfor overhead single polem'ounting at said group, three stationaryinsulators oii the'stiucture', contacts o'n-saidinsulators,said

contacts respectively being connected with said line terminals, threerotary insulators carried upon said structure, conductive switch bladescarried respectively by said rotary insulators, stationaryinterconnected conductive means between said rotary insulators, saidstationary conducting means being constituted by a rigid bus barconstruction having relatively rotary connections with said rotaryinsulators respectively and being supported and held therebyindependently of any fastenings to said structure, movable connectionsbetween all of said switch blades and said stationary conductive means,said movable connections being constituted by brush means, one each ofsaid switch blades being rotary into and out of engagement with thecontacts respectively connected with said line terminals for the firstcircuit and the other switch blade being rotary into and out ofengagement with the contact connected with the line terminal of thesecond circuit, and individual operating means for individually rotatingeach of said rotary insulators from a single operating station adjacentthe pole at ground level for individual connection or disconnection ofsaid line terminals.

2. Apparatus made according to claim 1, wherein all of said insulatorsare upstanding from a horizontal common platform formed by saidstructure and wherein two of said switch arms are operative to swing ina common substantially horizontal first plane and the third switch armswings in a second plane elevated relative to the first plane.

3. Sectionalizing switch gear for use at a group of three overhead lineterminals two of which are in a first loop circuit and one of which isin a second feeder or tap circuit; comprising a single structure adaptedfor overhead single-pole mounting at said group, three stationaryinsulators on the structure, contacts on said insulators, said contactsrespectively being connected with said line terminals, three rotaryinsulators carried upon said structure, said stationary insulators beinglocated at the corners of a triangle and the rotary insulators beinglocated within the boundaries of said triangle, conductive switch bladescarried respectively by said rotary insulators, stationaryinterconnected conductive means between said rotary insulators, movableconnections between all of said switch blades and said stationaryconductive means, one each of said switch blades being rotary into andout of engagement with the contacts respectively connected with saidline terminals for the first circuit and the other switch blade beingrotary into and out of engagement with the contact connected with theline terminal of the second circuit, and individual operating means forindividually rotating each of said rotary insulators from a singleoperating station adjacent the pole at ground level for individualconnection or disconnection of said line terminals.

4. Sectionalizing switch gear for use at a group of three overhead lineterminals two of which are in a first loop circuit and one of which isin a second feeder or tap circuit; comprising a single structure adaptedfor overhead single-pole mounting at said group, three stationaryinsulators on the structure, contacts on said in sulators, said contactsrespectively being connected with said line terminals, three rotaryinsulators carried upon said structure, all of said insulators beingupstanding from a horizontal common platform formed by said structure,said stationary insulators being located at the corners of a triangleand the rotary insulators being located within the boundaries of saidtriangle, conductive switch blades carried respectively by said rotaryinsulators, stationary interconnected conductive means between saidrotary insulators, movable connections between all of said switch bladesand said stationary conductive means, one each of said switch bladesbeing rotary into and out of engagement with the contacts respectivelyconnected with said line terminals for the first circuit and the otherswitch blade being rotary into and out of engagement with the contactconnected with the line terminal of the second circuit, two of saidswitch arms being operative to swing in a common substantiallyhorizontal first plane, and the third arm being operative to swing in asecond plane elevated relative to the first plane, and individualoperating means for individually rotating each of said rotary insulatorsfrom a single operating station adjacent the pole at ground level forindividual connection or disconnection of said line terminals.

References Cited in the file of this patent UNITED STATES PATENTS

